package com.atguigu.java1;

import java.io.File;
import java.io.FileInputStream;
import java.util.Date;
import java.util.Scanner;

import org.junit.Test;

/*
 * 一、异常体系结构
 *
 * java.lang.Throwable
 * 		|-----java.lang.Error:一般不编写针对性的代码进行处理。
 * 		|-----java.lang.Exception:可以进行异常的处理
 * 			 |------编译时异常(checked)
 * 					|-----IOException
 * 						|-----FileNotFoundException
 * 					|-----ClassNotFoundException
 * 			 |------运行时异常(unchecked/RuntimeException)
 * 					|-----NullPointerException
 * 					|-----ArrayIndexOutOfBoundsException
 * 					|-----ClassCastException
 * 					|-----NumberFormatException
 * 					|-----InputMismatchException
 * 					|-----ArithmeticException
 *
 * 面试题：常见的异常都有哪些？举例说明
 */
public class A1ExceptionTest {
    //******************以下是编译时异常***************************
    //FileNotFoundException
    //IOException
    @Test
    public void test7() {
		File file = new File("hello.txt");
//		FileInputStream fis = new FileInputStream(file);
//
//		int data = fis.read();
//		while(data != -1){
//			System.out.print((char)data);
//			data = fis.read();
//		}
//		fis.close();
    }

    //******************以下是运行时异常***************************
    //ArithmeticException
    @Test
    public void test6() {
        int a = 10;
        int b = 0;
        System.out.println(a / b);
    }

    //InputMismatchException
    @Test
    public void test5() {
        Scanner scanner = new Scanner(System.in);
        int score = scanner.nextInt();
        System.out.println(score);
        scanner.close();
    }

    //NumberFormatException
    @Test
    public void test4() {
        String str = "123";
        str = "abc";
        int num = Integer.parseInt(str);
    }

    //ClassCastException
    @Test
    public void test3() {
        Object obj = new Date();
        String str = (String) obj;
    }

    //IndexOutOfBoundsException
    @Test
    public void test2() {
        //ArrayIndexOutOfBoundsException
		int[] arr = new int[10];
		System.out.println(arr[10]);

        //StringIndexOutOfBoundsException
        String str = "abc";
        System.out.println(str.charAt(3));
    }

    //NullPointerException
    @Test
    public void test1() {
//		int[] arr = null;
//		System.out.println(arr[3]);

        String str = "abc";
        str = null;
        System.out.println(str.charAt(0));
    }
}
